People always want to know about sewage. No, it doesn't go into the river. Every boat has a holding tank. Every few days, one of these guys from the marina pumps out your tank using this hose. It connects your tank to a fitting on the dock. The man pushes a remote control, and the sucker at the end of the dock - one of those white units in the center background, pumps your sewage into the city sewage system. I said these were amazing docks! Gray water goes into the river.